List of top Physics Questions

Determine Min. Energy released when an electron jumps to ground state in Balmer series from infinity.

A liquid drop of radius R is divided into 27 identical drops. If the surface tension of the drops is T, then find work done in this process.

Find minimum deviation in a thin prism if refractive index \(μ = cot\bigg(\frac{A}{2}\bigg)\). Here \(A\) represents the angle of prism.

Determine ratio of de broglie wavelength of \(α- particle\) and proton of same kinetic energy is

A uniform disk of mass \(50\) \(kg\) is rolling without slipping with a speed of \(0.4 \;m/s\). Find minimum energy required to bring the disk to rest (in \(J\)).

A stationary hydrogen atom deexcites from first excited state to ground state. Find recoil speed of hydrogen atom up to nearest integer value.
(mass of hydrogen atom = \(1.8 \times 10^{-27}\) \(kg\))

In the system shown below, the pulley \(4\) string are ideal. If the acceleration of blocks is \(\frac{g}{8}\) , find \(\frac{m_1}{m_2}\)

The magnetic flux through a loop varies with time as \(Φ= 5t^2 -3t +5\). If the resistance of loop is \(8\) , find the current through it at \(t = 2\) \(s\)

Radius of curvature of equiconvex lens is 20 cm. Material of lens is having refractive index of 1.5. Find image distance from lens if an object is placed 10 cm away from the lens.

In a photoelectric experiment, frequency \(f = 1\).\(5f_0\) (\(f_o\): threshold frequency). If the frequency of light is changed to \(\frac{f}{2}\), then photocurrent becomes (intensity of light has doubled)

Unpolarised light incident on transparent glass at incident angle 60°. If reflected ray is completely polarized, then angle of refraction is

If the current through an incandescent lamp decreases by 20%, how much change will be there in its illumination?

Consider the circuit shown : The ammeter reads 0.9 A. Value of R is

In a given circuit, an ideal battery is connected with four resistances as shown. Find current \(i\) as mentioned in the diagram.

Consider a rod moving in a magnetic field as shown:

The induced emf across the ends of the rod is

Alternating voltage and current in circuit is given as \(V = (100 \;sin \;ωt)\) volt
\(I = 100\;sin\bigg(ωt+\frac{π}{3}\bigg)mA\)
Find average power dissipated in circuit.

Two charged particles A and B have charge q each while masses are \(m_1\) & \(m_2\). Both have the same velocity v and enter into a transverse magnetic field B such that their radii are \(r_1\) & \(r_2\). Then the ratio \(m_1 : m_2\) is

In a simple pendulum of length 10 m, the string is initially kept horizontal and the bob is released. 10% of energy is lost till the bob reaches the lowest position. Then find the speed of the bob at the lowest position.

Two forces \(F_1\) and \(F_2\) are applied on two rods \(P\) and \(Q\) of same materials such that elongation in rods are same. If ratio of their radii is \(x : y\) and ratio of length is \(m : n\), then ratio of \(F_1 : F_2\) is

A uniform wire has length L and radius r. It is acted on by a force F as shown. The elongation is l. If F and r are both halved, the new elongation will be :

The truth table for the combination of logical gates

Find the ratio of the charge on \(4\) \(µF\) to that on \(2\) \(µF\) in steady state.

A ball of mass \(120\) \(g\) moving with initial velocity \(25 \;m/s\) is stopped by an external force \(F\) in \(0.15\) \(sec\). Find value of \(F\) in newton :

Find the number of significant digits in the value 10.05

Two trains run on North-South parallel tracks. Train A moves with velocity 20 m/s towards North and train B moves with velocity 30 m/s towards South. Then find the velocity of train B with respect to train A